摘要 |
A multiple sample needle assembly includes a housing with a chamber therein. A first cannula for insertion into a liquid source is in fluid communication with the chamber. A second cannula is movably positioned in the housing and is out of liquid communication with the chamber when in a first position. A liquid flow mechanism inside the chamber is operatively responsive to inward movement of the second cannula to a second position for allowing liquid to flow from the chamber into the second cannula. After the liquid has been collected, the flow control mechanism automatically returns the second cannula to the first position. |